PubMed Health⌕ Search

Biomedical subjects

Y Nohara

Publications and source records attributed to Y Nohara.

At least 37 records · Page 2Linked to original sources

Distraction rod instrumentation with posterolateral fusion in isthmic spondylolisthesis. 53 cases followed for 18-89 months.

Fifty-three cases of isthmic spondylolisthesis were treated with distraction rod instrumentation and posterolateral fusion with or without nerve root decompression, and they were followed for an average of 39 months. Thirty-one cases without neurologic deficit were treated with instrumentation and fusion only. In 22 cases of predominant sciatic pain with neurologic deficit signs, nerve root decompression and instrumentation with fusion were conducted. The results showed a 90.6% solid union rate with satisfactory clinical improvement. Realignment of the vertebral displacement such as reduction of olisthesis and widening of the olisthetic disc spaces was obtained to some extent. No serious complications were encountered.

Adolescent↗

Primary myxedema with thyrotrophin-binding inhibitor immunoglobulins. Clinical and laboratory findings in 15 patients.

In a screening of 43 patients with primary myxedema, 9 patients were found to have IgG that inhibits the binding of 125I-thyrotrophin to its receptor (thyrotrophin-binding inhibitor immunoglobulins). Preparations of IgG from these patients did not stimulate thyroidal cyclic adenosine monophosphate generation and blocked thyroid stimulation by thyrotrophin in vitro. Clinical and laboratory features of 15 patients with this inhibitor, including 6 who were previously known, were compared with those of patients without the inhibitor. The patients with inhibitor, 2 men and 13 women, had onset of their hypothyroidism from age 2 to 49 years, and thyroid uptake in these patients was significantly lower than that in patients without inhibitor. Transient hypothyroidism was seen in all 5 infants born to 4 mothers having potent inhibitor immunoglobulins. These clinical findings indicate that thyrotrophin-receptor-blocking antibodies play a pathogenic role in a group of patients with primary myxedema.

Adolescent↗

Emergence of permanent teeth and onset of dental stages in Japanese children.

The purpose of the present cross-sectional study was to provide mean times of emergence of permanent teeth and onset of dental stages in Japanese children. A total of 1819 schoolchildren aged 6-15 yr were recorded. The results demonstrated specific sequences of emergence in the two arches and earlier emergence times in girls than in boys, both findings in keeping with investigations on other ethnic groups. Secular trend in tooth emergence was studied by comparing the results with data on Japanese children in 1934. The comparison revealed earlier mean times of emergence in general in contemporary Japanese.

Adolescent↗

Prolactin response to thyrotropin-releasing hormone in children with gynecomastia, premature thelarche and idiopathic precocious puberty.

Plasma prolactin (PRL) response to synthetic thyrotropin-releasing hormone (TRH) was studied in six patients with pubertal gynecomastia, five patients with premature thelarche and nine female patients with idiopathic precocious puberty. The basal concentration of plasma PRL was higher (p less than 0.01) in pubertal gynecomastia as compared to control, while baseline plasma PRL levels in premature thelarche and idiopathic precocious puberty were similar to those in controls. Plasma PRL level after TRH in patients with pubertal gynecomastia was higher (p less than 0.01) than that in control, while plasma PRL responses to TRH in idiopathic precocious puberty and premature thelarche were comparable to those controls. The TRH-induced PRL release was more enhanced during treatment with cyproterone acetate (CA) than before CA therapy in four of five patients with idiopathic precocious puberty. These data suggest that the enhanced release of PRL may, at least in part, contribute to breast enlargement in pubertal gynecomastia and that seen in idiopathic precocious puberty and premature thelarche may not depend on the PRL secretion. The prolonged administration of CA enhances the PRL responsiveness to TRH.

Adolescent↗

A case of insulin resistance associated with acanthosis nigricans.

We described here a 12-year-old male patient with the syndrome of insulin resistance and acanthosis nigricans type A. Insulin levels at fasting state and after glucose loading were 149 +/- 63 microU/ml (mean +/- S.D.) and over 1,000 microU/ml respectively, while the fasting level of blood glucose was 77.7 +/- 8.9 mg/ml (mean +/- S.D.). A marked resistance to exogenous insulin was observed. Circulating levels of insulin antagonists such as growth hormone, cortisol and glucagon were within the normal range. Proinsulin was less than 5% of the radioimmunoassayable insulin. No insulin antibody or antireceptor antibody was detected. Insulin binding to mononuclear cells was decreased to about 50% of the controls. Analysis of membrane receptors demonstrated the normal average affinity, dissociation kinetics and negative cooperativity with a decreased number of receptors. After two days fasting, plasma IRI levels decreased to 27 microU/ml, while insulin binding kinetics were not affected; which suggests that the receptor decrease was not secondary to hyperinsulinemia. These findings indicate that the decreased number of receptors was one of the causes for insulin resistance in this patient.

Acanthosis Nigricans↗

Posterolateral fusion with instrumentation in the symptomatic failed back patients.

Thirty-two symptomatic failed back patients after lumbar spine surgery performed for disc lesions underwent posterolateral fusion involving an adaptation of two distraction rod or combined distraction and compression rod instrumentation following decompression procedure when necessary. The main causative pathology of persistent pain was segmental instability with or without nerve root entrapment. The average follow-up period was 35 months. Twenty-eight patients responded that they were satisfied with the final operation. Fusion rate was 100% at the present study. The salvage instrumentation surgery to the failed back was thought to have brought about removal of instability, restoration of the disc height to some extent and decompression in some cases.

Adult↗

[Computed tomography in lumbar degenerative disease].

We reported the 18 patients which underwent surgical exploration and reviewed these CT findings. Method. All CT scans were obtained on Somatom II, high resolution CT scanner, with the patient in the supine position. A lateral localizer image (Topogram) was used to select the appropriate intervertebral disk space. The slice thickness was 4 mm. Results. CT findings in lumbar degenerative diseases include bony canal stenosis (central canal stenosis, narrowed lateral recess), soft tissue abnormalities (herniated nucleus pulposus, bulging annulus, hypertrophy and/or ossification of ligamentum flavum, no delineation of nerve root in lateral recess), and spinal instability (spondylolisthesis, vacuum phenomenon). The above three factors contribute to narrowing of spinal canal. No delineation of nerve root or soft tissue replacement of epidural fat in lateral recess suggests that the nerve root may be compressed by some factors. Herniated nucleus pulposus may cause nerve root compression with or without canal stenosis. Conclusion. This study revealed that the CT findings correlated closely with the surgical findings and the site of nerve root compression could be determined.

Adult↗

Inhibition of thyrotropin-induced adenosine 3'5'-monophosphate increase by immunoglobulins from patients with primary myxedema.

Immunoglobulin G (IgG) fractions prepared from the serum of 18 patients with primary myxedema, 9 patients with goitrous Hashimoto's thyroiditis, and 14 normal controls were tested for their ability to alter TSH stimulation of cAMP production in cultured human thyroid cells and the binding of TSH to its receptor. When compared with the cAMP increase induced by 0.1 mU/ml bovine TSH in the presence of normal IgG, cAMP accumulation was significantly inhibited (P less than 0.005) by the addition of IgG from patients with primary myxedema. TSH-induced cAMP accumulation was not affected by IgG from patients with goitrous thyroiditis. IgG from patients with primary myxedema also inhibited the cAMP increase induced by thyroid-stimulating immunoglobulins, but not against the increase induced by prostaglandin E1. None of the IgG tested affected the basal level of cAMP. Two potent inhibitory IgG were strongly positive for TSH-binding inhibitor immunoglobulins. Excluding these, no significant correlation was found between the thyroid stimulation-blocking activity and the TSH-binding inhibitory activity. These data suggest the presence of at least two different types of antibodies in primary myxedema which block adenylate cyclase stimulation by TSH and might be responsible for thyroid dysfunction and atrophy.

Adenylyl Cyclase Inhibitors↗

President lecture. Observations on myocardial ischemia.

Several problems in myocardial ischemia are discussed based on our experimental and clinical studies. Histochemical changes of the myocardium of adult mongrel dogs with a coronary artery ligation were as follows: The most noticeable findings were a decrease of phosphorylase activity in the pericapillary region of the infarcted area and an enlargement of the discoloration area due to fusion according to the prolongation of the ligation period. This may be explained by the fact that ischemic process takes place around the pericapillary zone in the early stage due to an arborescent distribution of the vascular system in the myocardium. This is presumed as one of the factors which induces heterogeneity of the ischemic myocardium. The reversibility of the injured myocardium due to ischemia was investigated electron-microscopically. The time limit of the myocardial reversibility from ischemic damage was 30 to 50 min. Characteristic changes of LDH isoenzymes and the pathohistological changes of the myocardium after ligation and reperfusion of the coronary artery were as follows: a) A decrease of the LD5 (H subunit) fraction degeneration of the myocardial fibers, fibrosis of the connective tissue and scar formation took place. b) The minimum value of LD5 (H subunit) was observed in cases with a 7-day ligation in the ligation group and in cases with a 12-hour ligation which was followed by a 7-day reperfusion in the reperfusion group. c) The time to reach the minimum LD5 value differed between these 2 groups. The most probable cause of this difference is the protection of the myocardium by reperfusion. 4) In 24 dogs 20 mCi 99mTc-PYP was injected intravenously one and a half hours before the reopening of the chest. Then, Tc-PYP images were obtained at frontal and left lateral views. Tc-PYP images of each cross-sectional surface were also obtained. In the ligation group, 99mTc-PYP uptake in the ischemic myocardium was demarcated clearly in cases with a 1-7 day ligation. In the reperfusion group, 99mTc-PYP uptake in the ischemic area was clearly noticed in cases with a 12-hour to 6-day ligation, which was followed by a 1- to 7-day reperfusion. When the period of the reperfusion was prolonged, it became more difficult to obtain a positive image. In 14 patients with acute myocardial infarction Tc-PYP scintigrams were studied with reference to their ECG.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Exercise parameters for the prediction of post-training increase in exercise tolerance in patient with stable angina pectoris.

Twenty cases with effort angina underwent exercise training for a mean follow-up period of 38 weeks. Various parameters were investigated to clarify whether or not such parameters can be used to predict an increase in exercise tolerance of patients with effort angina. The increase of exercise tolerance after training was found to be related to a reduction of the myocardial oxygen demand at a given external work load. The maximal heart rate (max HR) the maximal systolic blood pressure (max SBP) and the maximal rate-pressure product (max RPP) could not predict the post-training increase in exercise tolerance. Before training, the maximal oxygen intake (VO2max) was found to be lower, and the HR/VO2max and the SBP/VO2max were higher in the group (11 patients) which showed a good response to the exercise program (effective group) than those in the group (9 patients) which did not (unchanged group). Before training, the HR/VO2max and the SBP/VO2max in the effective group were also higher than those of 96 healthy adults. On the other hand, the HR/VO2max and the SBP/VO2max in the unchanged group were not different from those of the healthy adults throughout the training. It is useful to compare the values of the HR/VO2max and the SBP/VO2max of patients with effort angina to those of healthy adults for the prediction of post-training increase in exercise tolerance.

Angina Pectoris↗

Plasma prolactin response to thyrotropin releasing hormone in children with newly diagnosed insulin dependent diabetes.

The basal and TRH-induced prolactin (PRL) and TSH secretions were examined in 14 children aged 4 to 13 years with newly diagnosed insulin dependent diabetes (IDD) within three weeks after diagnosis. Basal PRL levels did not differ from the values of control. In response to TRH, 6 out of 14 patients showed an exaggerated PRL response and 8 a normal PRL response. The basal and TRH-induced TSH secretions were normal, while plasma triiodothyronine (T3) and thyroxine (T4) concentrations were significantly (p less than 0.001, p less than 0.02) lower in patients than in controls. These findings suggest that a significant proportion of children with newly diagnosed IDD has an exaggerated PRL response to TRH, and TSH secretion remains unchanged despite significant decreases of circulating thyroid hormone levels.

Adolescent↗

Epidemiologic survey of juvenile-onset insulin dependent diabetes mellitus (IDDM) in Hokkaido, Japan, 1973-1981.

An epidemiological survey of juvenile-onset insulin dependent diabetes mellitus (0-15 years) was performed in Hokkaido, Japan, during 1973-1981. The mean annual incidence during the nine year period was 1.26 per 100,000 and showed a significant increasing trend. The prevalence of IDDM at the ages of 0-15 and 6-15 were 7.7 and 11.7 per 100,000 respectively. These figures were much lower than those previously reported in Caucasians. Peaks in incidence were seen from February to April, and a reduction in incidence from July to September. The females showed a bimodal distribution with the peak incidence at 10 to 12 years and with a smaller peak at about 7 years. The males showed a broad single peak at about 10 to 13 years.

Adolescent↗

Protection of the ischemic myocardium with calcium antagonistic drugs.

Ligation of the coronary artery to produce myocardial infarction experimentally was performed in 41 mongrel dogs. The dogs were then treated with niludipine or nifedipine. Niludipine in doses of 0.05 mg/kg/day (niludipine A group) and 0.1 mg/kg/day (niludipine B group) or nifedipine 0.05 mg/kg/day (nifedipine group) was administered for 7 postoperative days. The animals were sacrificed, their hearts removed and extent of myocardial damage studied. 1. The size of infarctions measured by 99mTc-PYP myocardial scintigrams of the isolated heart was significantly smaller in the niludipine A group. 2. The degree of ischemia indicated by LDH isoenzyme patterns was lowest in the niludipine A group followed by nifedipine and niludipine B group in this order. The value for H subunits of LDH isoenzymes on the subepicardial side was higher in the nifedipine group. 3. Histopathological findings varied from specimen to specimen, but in general the niludipine A group showed best improvement. Our results suggest that the calcium antagonistic drugs, niludipine and nifedipine, seem to have myocardium protective properties in dogs. To what degree these findings can be applied clinically needs further studies.

Angiocardiography↗

Elastofibroma in Okinawa. A clinicopathologic study of 170 cases.

A clinicopathologic study was made of 170 cases of elastofibroma detected in Okinawa Prefecture, Japan. A majority of the cases of elastofibroma were detected in the mainland of Okinawa and its offshore islands Tonaki-jima and Aguni-jima. The 21 cases from Tonaki Island had a familial occurrence. Simultaneously, 55 of the total cases were recognized to have occurred within the same family lines. Besides the growth of elastofibroma in the subcapsular region, there was a high rate of growth in the infraolecranons area. A case of multiple elastofibroma including the lateral thoracic wall as well as the ischial tuberosities, was also studied. In this disease, there was found to be an excessive amount of elastic material produced by fibroblasts as well as obstacles in the course of forming elastic fibers. Therefore, it was considered that this tendency was a sort of reactive hyperplasia taking place with a constitutional predisposition in the background. All cases should undergo biopsy to rule out sarcoma. No other treatment is necessary in asymptomatic patients. Local excision is all that is necessary in those with pain.

Adult↗